California state Senator Roderick Wright plans to resign from office later this month following a perjury and voter fraud conviction that saw him sentenced to 90 days in jail, he said in a letter sent on Monday.

Wright, who was convicted in January of lying about whether he lived in the district he sought to represent, was the first of three California Senate Democrats to face criminal proceedings this year. This effectively cost the party a cherished two-thirds majority in the California Senate.

A Los Angeles Superior Court judge sentenced Wright on Friday to 90 days in jail and said he was no longer eligible to hold office in California.

“Effective Sept. 22, 2014, I hereby resign from the California State Senate,” the Los Angeles-area Democrat wrote in a letter to the secretary of the legislative body on Monday, three days after his sentence was handed down.

California state Senate Democratic leader Darrell Steinberg had urged Wright on Friday to resign, saying he was free to appeal his case as a private citizen. A Steinberg spokesman said Steinberg had accepted Wright’s pending resignation.

Candidates for U.S. Congress are not required to live in their districts, but state lawmakers are mandated to do so under California law. Prosecution under the law is somewhat rare, however.

Wright, whose lawyer has said he plans to appeal the conviction, owned a home in the working-class suburb of Inglewood, which is part of his legislative district, but lived in the affluent Baldwin Hills neighborhood of Los Angeles.

He had contended that a state law requiring lawmakers to keep domiciles in their districts allows candidates to reside elsewhere. Both the jury and judge in the case rejected that distinction.

Wright was the first of three Democratic state senators embroiled in separate criminal cases in California to announce their resignations, a move welcomed by the Senate Republican leadership. All three were suspended with pay earlier this year.

Senator Leland Yee of San Francisco was indicted on racketeering, wire fraud and conspiracy charges, and Senator Ron Calderon is fighting two dozen counts of bribery, fraud, money laundering and conspiracy.

On Monday, state Assemblyman Isadore Hall, a Democrat who represents an area that partly overlaps Wright’s senate district, said in a statement he would run for Wright’s seat in a special election expected to be held within the coming months.